Removed F6. Moved F7 to leader. Added autochdir.
Remove function key mappings; changed some others.

F4 becomes ,nt (NERDtree toggle).
F5 becomes ,bl (buffer list).
F8 becomes ,vl (.vimrc load).
F9 becomes ,cw (clean whitespace from file).
S-F9 becomes ,cl (clean whitespace from line).
,ev becomes ,ve
,n becomes ,nh
,r becomes ,rr
,s becomes ,ss
,w becomes ,ww
Added Ctrl-z. Changed ,tl to ,sw.

Removed color column from help.